DE370232C - System arrangement for vacuum tubes with anode, grid and glow cathode - Google Patents

Description

There are two types of vacuum tubes with hot cathodes that have been used up to now differ in principle from system arrangements. In the original form the hot cathode is simply opposite the anode. This type of arrangement is indicated schematically by Fig.

ι means the filament, 2 the arbitrarily designed, z. B. round anode. Was a

ίο grid used, this was for example in the form of a frame 3, which is covered in a grid or sieve shape with fine wire was placed between the anode and the hot cathode. "The doubling of this

Order "is known, so that ζ. Β. Accordingly the grid 3 drawn to the left of the anode in Fig. 1 is another of this independent grid and, corresponding to the left filament 1, also on the right Another filament has been placed on the side. With this arrangement, a common anode for two discharge lines, which are controlled by independent grids. Except this one pure juxtaposition of the system parts according to Fig. 1 are the arrangements according to Albb. 2a "and 2lb are known. In Fig. 2a the filament 1 is inverted V-shaped in one Glass or metal frame 4 stretched around which the fine wire made of Grid 3 is wound around. The anodes usually consist of those indicated by dashed lines Metal sheets 2, which are arranged on both sides of the frame 4. Located here the glow ratio r is within the lattice and both inside the anode. A variant of this construction is the so-called cylindrical Arrangement (Fig. 2b), in which within an anode cylinder 2, for example spiral grid 3 is arranged, while the filament 1 usually axially through the system. Considered If the constructions mentioned are viewed from different points of view, they each have their own particular advantages and disadvantages. The arrangement according to

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Fig. Ι has the obvious advantage that the arrangement of the system parts is not offers the least technical difficulties, since the arrangement is independent of one another is. You can therefore design each of the parts as you like, in particular in any desired form. In addition, the tube is extremely easy to repair, if damage occurs. Because such damage usually occurs with normal use only on the filament, which after a certain burning time of usually blows a few hundred hours. Here it is sufficient for the construction according to Fig. 1, the plate-like foot from which the filament 1 is usually carried will melt out, replace the burned-out filament with a new one and to evacuate the tubes again. ao The arrangements according to Fig. 2 behave differently in this respect. It lights up without further ado that the replacement of a burned-out filament in the arrangement according to Fig. 2a is much more difficult, if not practically impossible. While the arrangement according to Fig. 2a is still a certain freedom with regard to the design of the • filament (straight, V-shaped, M-shaped or the like.), This possibility falls with the arrangement according to Fig. 2b away. Here the mechanical fastening of the grille is practically extraordinary difficult, since the grid lies within the anode cylinder 2 and is not accessible, especially in its central parts. The design of the filament itself can only take place in a straight line. as well is the question of a mechanically strong and vibration-free design for this Arrangement can hardly be solved satisfactorily in practice.

According to the present invention, it is proposed that the hot cathode is basically in this way to arrange that it surrounds the anode in whole or in part, in contrast to that Known a single uniform discharge path between the anode and the s.ie more or all around the hot cathode is present. The grid, or when in use several grids at least one of the same, so must be the space between the anode and completely separate the cathode surrounding it.

Fig.3 shows an example embodiment of the inventive concept. The hot cathode 1 surrounds the anode 2. The drum-like grid 3, for example, can be arranged between the two. In addition to great mechanical advantages, the filament is exposed here so that it is very easy to replace. The arrangement is also very advantageous in other respects, since the filament can be observed directly from all sides and, on the one hand, the permissible glow strength can always be correctly maintained, which causes difficulties in the closed constructions according to Fig. 2. Above all, ¹ you can also take the lamp out of operation if a point of the filament appears suspicious, and can thus avoid the very unpleasant short circuits that usually occur when the filament burns through contact with the grid and anode disrupt the whole system. You can easily connect several filaments in parallel or design the hot cathode as a band, etc., as shown in Fig. 3, or the hot cathode as a structure according to the same aspect, which is also an example of an embodiment, is shown in Fig. 4 in a side view .

The filament 1 is inverted V-shaped here guided and somehow held from above by means of the device 5. The grid is applied to the support 6, of which also 'at the same time the approximately roof-shaped or triangular-shaped anode 2 can be carried. Here, too, the hot cathode surrounds the anode. A particular advantage of this construction is that the capacity of the grid can be chosen extremely small, whereby the sensitivity of the tubes for both transmitting and receiving purposes is extraordinary is increased.

Claims (2)

Patent Claims: 1. System arrangement for vacuum tubes with anode, grid and hot cathode, characterized in that the hot cathode wholly or completely the anode with the formation of a single discharge path partially surrounds. 2. System arrangement for vacuum tubes according to claim 1, characterized in that that the grid, or if several grids are used, at least one of the same between the anode and no the hot cathode surrounding it more or on all sides and the uniform overcharge path between The anode and cathode are completely separated. 1 sheet of drawings.